Home
Class 11
PHYSICS
A tuning fork of frequency 512 Hz makes ...

A tuning fork of frequency 512 Hz makes 4 beats per second with the vibrating string of a piano. The beat frequency decreases to 2 beats per sec. when the tension in the piano string is slightly increased. The frequency of the piano string before increasing the tension was

A

(A) 510 Hz

B

(B) 514 Hz

C

(C) 516 Hz

D

(D) 508 Hz

Text Solution

Verified by Experts

The correct Answer is:
D
For tuning fork `f _(A) =512 Hz`
For piano wire, `f _(B) = 516 OR 508 Hz `
`(because ` Initially beat frequency is 4 beat/second)
When tension is increased in piano wire, new beat frequency `f _(A) - f._(B)` becomes 2 Hz.
When tension in increased, frequency of piano wire increase. Hence `f ._(B) gt f _(B)`
Moreover `f _(A) - f._(B) =2 `
`therefore f _(B) = 508 Hz and f._(B) = 510 Hz`
So that `(i) f _(A) - f _(B) = 512 - 508 = 2 Hz`
As per the statement, Thus, `f _(B) = 508 Hz`
Note Here `f _(B) ne 516 ` because `f ._(B) gt f _(B)` and so `f ._(B) -f_(A) gt 4 Hz` which would be wrong as it is not so in the statement.
Promotional Banner

Topper's Solved these Questions

  • WAVES

    KUMAR PRAKASHAN|Exercise SECTION-F (Questions From Module) (Sample questions for preparation of competitive exams)|23 Videos

  • WAVES

    KUMAR PRAKASHAN|Exercise SECTION-D (NCERT Exemplar Solution) (Long Answer Type Questions)|5 Videos

  • UNITS AND MEASUREMENT

    KUMAR PRAKASHAN|Exercise Section -F (Questions from Module )|20 Videos

  • WORK, ENERGY AND POWER

    KUMAR PRAKASHAN|Exercise QUESTION PAPER (SECTION - D)|1 Videos

Similar Questions

Explore conceptually related problems

A tuning fork of known frequency 256 Hz makes 5 beats per second with the vibrating string of a piano. The beat frequency decreases to 2 beats per second when the tension in the piano string is slightly increased. The frequency of the piano string before increasing the tension was

Two tuning forks having frequency 256 Hz (A) and 262 Hz (B) tuning fork. A produces some beats per second with unknown tuning fork, same unknown tuning fork produce double beats per second from B tuning fork then the frequency of unknown tuning fork is :-

A column of air at 51^(@) C and a tuning fork produce 4 beats per second when sounded together. As the temperature of the air column is decreased, the number of beats per second tends to decrease and when the temperature is 16^(@) C the two produce 1 beat per second. Find the frequency of the tuning fork.

A string 25cm long and having a mass of 2.5 gm is under tension. A pipe closed at one end is 40cm long. When the string is set vibrating in its first overtone and the air in the pipe in its fundamental frequency, 8 beats per second are heard. It is observed that decreasing the tension in the string decreases beat frequency. If the speed of sound in air is 320m//s , find the tension in the string.

Tuning fork A has frequency 256 Hz. It produces 4 beats per second with fork B. When the prongs of fork B are rubbed little, it produces 2 beats per second with A. Find out frequencies of foek B, before and after rubbing its prongs.

A vibrating string of certain length l under a tension T resonates with a mode corresponding to the first overtone (third harmonic ) of an air column of length 75 cm inside a tube closed at one end. The string also generates 4 beats//s with a tuning fork of frequency n . Now when the tension of the string is slightly increased the number of beats reduces to 2 per second. Assuming the velocity of sound in air to 340 m//s , the frequency n the tuning fork in H_(Z) is (a) 344 (b) 336 (c ) 117.3 (d) 109.3

A tuning fork A, marked 512 Hz, produces 5 beats per second, where sounded with another unmarked tuning fork B. If B is loaded with wax the number of beats is again 5 per second. What is the frequency of the tuning fork B when not loaded ?

Four tuning forks of frequencies 200,201,204 and 206 Hz are sounded together. The beat frequency will be

Two turning forks of frequencies n_(1) and n_(2) produces n beats per second. If n_(2) and n are known, n_(1) may be given by

Two sitar wires A and B producing the note "Dha" are slightly out of tune and produce 5 beats per second. When the tension in the wire B is slighly increased, the beat frequency decreases to 3 Hz. If frequency of A is 512 Hz, what should be original and final frequency of B ?

KUMAR PRAKASHAN-WAVES-SECTION-E (Multiple Choice Questions (MCQs)) (MCQs asked in Gujarat Board and Competitive Exams)
  1. Each of the two strings of length 51.6 cm and 49.1 cm are tensed separ...

    Text Solution

    |

  2. A transverse wave is represented by y = Asin(omegat - kx). For what va...

    Text Solution

    |

  3. A tuning fork of frequency 512 Hz makes 4 beats per second with the vi...

    Text Solution

    |

  4. Two waves are represented by the equations y (1) = a sin (omega t + k...

    Text Solution

    |

  5. Sound waves travel at 350 m/s through a warm air and at 3500 m/s throu...

    Text Solution

    |

  6. Two identical piano wires kept under the same tension T have a fundame...

    Text Solution

    |

  7. A wave travelling in the +ve X-direction having maximum displacement a...

    Text Solution

    |

  8. If n (1), n (2), and n (3) are the fundamental frequencies of three s...

    Text Solution

    |

  9. The fundamental frequency of a closed organ pipe of length 20 cm is eq...

    Text Solution

    |

  10. A source of sound S emitting waves of frequency 100 Hz and an observer...

    Text Solution

    |

  11. For a string, tied with two fixed rigid supports, scparated by 75 cm h...

    Text Solution

    |

  12. A siren emitting a sound of frequency 800 Hz moves away from an observ...

    Text Solution

    |

  13. For one resonance tube, a tuning fork produces resonance when air colu...

    Text Solution

    |

  14. A uniform rope of length L and mass m, hangs vertically from a rigid s...

    Text Solution

    |

  15. The second overtone of an open organ pipe has the same frequency as th...

    Text Solution

    |

  16. Three sound waves of equal amplitude have frequencies (n-1), n, (n + 1...

    Text Solution

    |

  17. When I m long metallic rod is vertically dropped it strikes the solid ...

    Text Solution

    |

  18. When two organ pipes with fundamental frequencies n(1) and n(2) are c...

    Text Solution

    |

  19. A tuning fork is used to produce resonance in a glass tube. The length...

    Text Solution

    |

  20. Fundamental frequency of one open pipe is equal to third harmonic of c...

    Text Solution

    |